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ALARM CLOCK.

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UNITED STATES PATENT OFFICE.

FRANK SHARPE, OF LONDON, ENGLAND.

ALARM-CLOCK.

SPECIFICATION forming part of Letters Patent No. 537,366, dated April 9, 1895.

Application filed July 11,1894:- Serial No. 517,227. (No model) To all whom it may concern:

Be it known that I, FRANK SHARPE, a subject of the Queen of England, residing at London, England,have invented certain new and useful Improvementsin or Relating to Alarm- Olocks and the Like, of which the following is a specification.

This invention relates to that class of alarm clocks and the like which are adapted to give two or more alarms at short or long intervals apart as required. The details of the mechanism would require to be varied according to the exigencies of the particular application, the following description in reference to the accompanying drawings serving to show how the invention may be applied to an alarm clock of ordinary construction.

In the drawings,Figure 1 is an elevation of sufficientof an alarm clock constructed according to this invention to illustrate myimprovements. Fig. 2 is a horizontal section on the line 22 of Fig. 1. Fig. 3 isa portion of a vertical section on the line 3-3 of Fig. 1. Figs. 4 and 5 are vertical sections taken respectively on the lines it--41: and 5-5 of Fig. 2. Fig. 6 is a view of portion of Fig. 2 as when one alarm has been released and the other has yet to be released, and Figs. 7 and 8 represent modifications hereinafter more particularly described.

Like letters indicate like parts throughout the drawings.

In carrying my invention into practice as shown in Figs. 1 to 6 of the accompanying drawings I employ a snail or cam A formed conveniently as a thick disk with a recess A Figs. 2 and 5 having a perpendicularsurface or step A at one side and a gradual rise A to the level of the face A of the snail A at the other side. This snail A is carried by or connected to say the wheel 13 of the clock and is caused to revolve at a suitable speed conveniently once in twelve hours. This snail Ais of substantially the same construction as the snails ordinarily used for a similar Facing this snail or cam disk A is an arrangement which may consist of a simple disk 0 with two or more pins, studs, steps or equivalent 0 O projecting from it and'facing the cam disk A; one or the other of these pins usually bearing against the face of disk A when the alarm is set. These pins 0 C are not in the same radial line but are arranged one more or less behind the other according to the intervals between the alarms to be given. The cam disk A and conveniently the toothed wheel 13 to which it may be connected are loose upon the arbor D on which is rigidly mounted the stud disk 0 and may be provided with a boss at its opposite face which bears upon a spring controlled or spring detent device E. This boss however is not shown in the accompanying drawings the spring detent device E being so arranged that but very little of its surface is in actual contact with the surfaceof the wheel B thereby attaining the same result, namely, reducing friction, which should be attained by the provision of the before mentioned boss.

The device E is provided with two detents E F. each adapted to release a separate alarm mechanism as hereinafter described. The detent E as regards its relation to the releasing arm F with which it is adapted to operate in conjunction, is shorter than the detent E appertaining to the arm F.

' hen the detent device E is allowed to move outward a certain distance it releases the detent E from the arm F but still retains the detent E in engagement with the arm F the detent E being subsequently disengaged from the arm F when the detent device is allowed to move outward to a further extent.

The detent device is conveniently formed of a flat spring E the lower ends of each branch of the fork being secured in any desired manner to the clock movement plate G and the upper part having outwardly extending arms E to which the detents E E may be secured by soldering or in anyother con venient manner. The spring E tends constantly tov move the detents E E out of engagement with the releasing arms F F respectively.

The arbor D may be fitted in the usual manner with a head D and an index or not, working over the dial to enable the disk O to be adjusted in any desired position according to the time at which it is desired the alarm should go off and any desired means such as a cupped spring D may be provided to take the thrust as caused by the spring E on the arbor D.

The operation is as follows: The cam disk A is revolved by the moving train of wheels of the clock in the usual manner and the stud disk 0 is turned by means of the knob or head D or in any other convenient manner to the position which will cause the alarm to go off at the desired time. As the cam disk A revolves the perpendicular edge A approaches the studs or steps 0 O and as soon as this edge passes the back edge of the stud O which up to that time is in contact with the face A the cam disk which has formerly been pressed to its rearmost limit slips forward as far as the second stud C will allow. This has the effect of removing the detent E out of the path of the arm F so as to release the first alarm mechanism H the hammer H of which is caused to strike the gong or bell (not shown in the accompanying drawings) in the usual way. As the cam disk A continues to revolve, the perpendicular edge A passes beyond the back edge of the stud C so that the cam disk A slips still farther forward and thereby disengages the detent E from the arm F so that the second alarm device H is released and its hammer H caused to strike the gong or hell; the interval between these two operations depending upon the distance 'that one of the pins 0 C is in advance or in the rear of the other.

It will be readily seen that considerable variations may be made in the details of the before described alarm clock without departing from the spirit of this invention. For example as shown in Fig. 7 the detents E and E instead of being connected together in the manner indicated in Figs. 1 to 6 may be formed separate from each other, or the cam disk A instead of rotating and the stud disk 0 being non-rotating the cam disk may be non-rotating and the stud disk rotated in any convenient manner. Again the shape of the disk may be modified. For example instead of forming a complete disk it may be in the form of a ring; or instead of providing it with only one step to operate in conjunction with two or more studs or steps 0, the, it may be provided with two or more such steps to operate in conjunction with one stud or step (0 or 0 Again, instead of using two detents E E I may arrange the arms F F (or as many more as may be necessary) adjacent to each other and effect their release at the desired intervals of time by one and the same detent as indicated for example in Fig. 8; this detent being the equivalent of the two detents E, E inasmuch as it performs the functions of both of them.

The two alarm devices II H may be conveniently operated by the same spring in any of the usual ways. The means for transmitting motion from the spring barrel to these devices however constitute no part of the present invention.

I claim In an alarm clock, the combination with the usual apparatus for operating an audible alarm, comprising two disks, one in operative connection with the clockwork, and means for adjusting the other in relation to the first, a spring tending to move one of the disks laterally, a projection or step on the face of one disk to prevent this lateral movement, a recess or step in the face of the other disk to receive the projection when the recess and. projection or two steps coincide to allow ot the lateral movement, a stop on one of the disks to limit said lateral movement, an arm in operative connection with the hammer, a detent for engaging and disengaging the arm and held in engagement with the arm by the laterally movable disk, and a spring for moving the detent out of engagement with the arm when the disk is moved laterally, of a second hammer gearing in operative connection with it and the clockwork mechanism, an armin operative connection with this second hammer, a detent for engaging and disengaging this arm and held in engagement with the arm by the laterally-movable disk, a spring for moving the detent out of engagement with the arm, and a second step in one of the disks to release the stop on the other and allow of the further lateral movement of the disk and consequent release of the second hammer, substantially as set forth.

In testimony whereof I have hereto set my hand in the presence of the two subscribing witnesses.

FRANK SHARP 1C.

Witnesses:

HARROLD WADE, HARRY B. BRIDGE. 

